Fading elimination



Ju y 1933. H. H. BEVERAGE Er AL 1,917,290

I FADING ELIMINATION Filed March 15, 1928 INVENTORS H.H.BEVERAGE BY .PETE SON AT RNE Y Patentedjuly 1 1, 1938 UNITE Di STATES HAnoLn a. B VERAGE] AND nAnoLn o ASSIGNORS T RADIO CORPORATION OF PATENT oFFIC'E a rnrrnnson, or n vnniinen, new YORK,

Annalee, a oorar'oaar on or DELAWARE rsmive nLIMniATIon r j v Application fired March 15, 1923. seriai-ntleemsv.

discloses the fact that difierent locations have diiferentfading characteristics and, there- 1'5 fore, it is conceivable that; signals might be 7 of a maximum intensity at one instant at an antenna =located-at one point and the same instant-be of a minimum intensity at .anantenna located at a pointmore or less '20 remote from said first point. 7 It was first .thought when considering-the above facts that it would be possible to combine signals from various antenna geographicallyspaced with respect to each other by directing their 2 separate energies to agoommon. receiver vand making fixed adjustments for phase displacements relative to each other of thesignal voltages fromthe separate antenna systems. However, this scheme had great limitations 0 inasmuch as it was found thatthe phase re-' lationship between the signal voltage received at one antenna and that received at another antenna changes from instant to lnstant.

It 1s, therefore, an obyect of our inven- 8 tion to provide a method and means of combining signals from various geographically separated antenna systems independent 'of the phase relationship between'the signals received on the separate antenna systems.

74 The broad idea ofthis scheme of combining signals has been disclosed in our copending application Serial No. 78,768, filed January 2,

1926, for which this'application represents a modification and further development of l the broad idea therein set forth. WVe have by the accompanying drawing illustrated one form which our invention may assume although, itis to be understooch thatvarious modifications such as fall within its spirit and scope may be resorted to in so faras ergy to connections 9 to 16 inclnsive. connections, 9 to 16 mclusive, maybe of regular contacttypeof connections or, as shown,

as to alternately; make and break a circuit 1, Energy-reaching the arm1l7 fromthe vari--' member upon the end they fallwithin the scope of the invention as defined bythe claims found at the endof this specification.

Referring now to the drawing, we' 'have shown a receiving system,in which, for convenience of illustration, eight separate antenna systems, 1 to 8', nclusive, have been ndicatedand areeach 'dlrectlng ;tl1611"(-3I1 The may preferablyconstitute one plate of a con denser member, the other plate of which is formed by the arm'17. '1 r p The arm '17 v 's mount d,as shown, upon the by aprime mover at. a, rapid ratelso that the end of-the, arm 17'wi11, rapidly passover the various connections 9 to 16 inclusive, so

by means of formingja capacity connection since the energy received, upon each ,of the separateantenna' systems, 1 {to 8, inclusive, is radio frequency energy, and the condenser offers little or no opposition ,to the flow of 1 current from the antenna system into the arm by' way of the plates, 9" to 16 inclusive,

whichsuccessively with the end of thearm 17' form a condenser unit.

ous antenna systems, 1 to 8 inclusive, is car-. ried'through a conductor 19 from a contact of the arm 17 or, if

desired, theend ofthe shaft 18, to ground at 21. Energy in the conductor 19 is directed into the primary winding 28 of a. transformer 22 and is transferred to the-secondary 24 from which it is directed to areceiving system 25.

It is thus seen that the'energy'from the, sep-g i arate antennae systems, 1 to inclusive, is thus fed into the receiving system at a periodical- ,ly and constantlyinterrupted rate so that the signals received upon the various antennae are all directed to the single receiving meansifi? Since the arm 17 is driven at a high rate of speed the signal efiects reaching any of the separate antenna systems are transferred at such a rate that several antenna systems are connectedwith the receiver for each Sigma/151 6 shaft or other rotary "member 18 and driven dot and there is. very little chance or possibility of this dot being entirely lost by fading since the chances that fading will occur in each of these antennae systems at the same instant is extremely remote. For this reason it can 'be'seenthat it is unnecessary in the case shown to have any regard for the phases of thesignals reaching the separate antenna systems, since at any instant only one antenna is connected with the receiver and consequently relative phases do not enter into the problem of combining energies. From the above it can be seen that the speed of r0- tation of the switching armj'17 forming the connecting link between the various antennae. l to'8 inclusive, and the receiver 1s a function of the speed of signalling and, theresystem and'mechanical means'fo r periodically associating'each of said antennae, one at a time, with said receiving system whereby said receiving system, ,at periodic intervals, receivers signal energy from each of said spaced antennaeindependently of thesignals reaching other. antennae therebysubstantially eliminating the effectsof fading;

*2Q'A system for eliminating the fading of signals radio signallingapparatus which includes, a plurality of geographically spaced antennasystems located at widely" separated points, a single receiving system'for all of said antenna" systems,'and mechanical means 'for successively connecting electrically said receiving system with each of said antenna,

systems'one at a time 7 'atfa predetermined speedy;

3. system for eliminating "the effects of fading radio signalling apparatus which includes, a plurality of geographically spaced antenna systems located at widelyseparated points, a single receiving system for all of said antenna systems, means for transmitting the energy from'said separated antenna systems to a common point and mechanical means located at said point and associated with said receiving means for successively,

switching said receiving meanslfrom'one of said antennae systems to another so that only 'one of said antenna systems is connected at one time with said receiving means.

4. A system: for eliminating the effects of fading in radio signalling apparatus which includes,'a plurality of geographically spaced antenna systems located at widely separated,

points, a' single receiving system for all of said antenna systems, means for transmitting the energyfrom said separated antenna systems to afcommon point and mechanical means located'at saidpoint for successively capacitively switching said receiving system from one of said antenna systemsto another so that only oneofsaid antennasystems is connected at a time'with said receiving system.- v -v p r '5. The method of radio reception for 'elimjinating fading efiects which'includes collecting energy at a plurality of geographically separated points, and mechanically "causing individual, successive and periodic transferbf the energy collected at each point'to areceiver, whereby the output thereof 'ismain- 1 tained at a substantially constant level. '1

6. In a system for reducing fading effects a. plurality of geographically separated-antennae located at widelylseparated points, and

a mechanically operable switch for coupling p each of the antennae successively and periodi- Cally one at atime toa receiver whereby the output thereof is maintained substantially constant and free from fading. Y

V I HAROLD H. BEVERAGE.

- HAROLD o; PETERS ON. 

